Field of the Invention
The present invention relates to a construction of a fiber matrix utilized for the protection of surface soils, subsurface soils, turf and vegetation typically disturbed by construction activities or eroded by the forces of falling and flowing water. Such fiber matrix may be identified as a permanent Rolled Erosion Control Product (RECP), termed a Turf Reinforcement Mat (TRM), which mat is utilized in conjunction with the vegetation to form a permanent, systemic installation that reinforces that vegetation, improving the overall resistance to nature's hydraulic forces and is based upon Provisional Application No. 62/283,276, filed 26 Aug. 2015, and incorporated herein by reference in its entirety.
Discussion of the Art
Disturbed ground is usually repaired and protected by the incorporation of natural vegetation on the site. However, in many cases, the accelerated or concentrated flow or steepened slopes caused by human development increases the forces of erosion, leaving the vegetation unstable. In these cases, a permanent Rolled Erosion Control Product (RECP), termed a Turf Reinforcement Mat (TRM), is used in conjunction with the vegetation to form a permanent, systemic installation that reinforces the vegetation, improving the overall resistance to hydraulic forces.
Uncontrolled erosion has an enormous impact on our environment, our water sources and on its maintenance and supply for agriculture resources and or maintenance and support of wildlife. Such effects have cost billions of dollars each year trying to manage or correct for those deleterious effects. Channels and waterways become filed with sediment, shorelines may be lost, and fertilizers may collect in water supplies to poison such water. Much of this may be irreversible. The use of RECPs, TRMs and sediment control barriers have become standard practice in the efforts to reduce polluted runoff into natural waterways and water supplies.
As a means to produce TRMs, a number of technologies have been developed and successfully deployed. Of this multitude of construction techniques, three stand out as the most widely adopted. These three technologies have been used more often and with more success than others.
The first of such technologies comprises stitch bonded, fiber matrix products which also serve as the most common technology. This method utilizes fiber that is chopped or cut, straight or crimped, and is placed atop a netting material as it proceeds down an assembly line. A second net is placed atop the fiber fill. The sandwiched arrangement travels further down the assembly line and is sewn by parallel stitching. The stitching secures the layers together and integrates the components into a single material. All of the component materials, fibers, netting and stitching, are typically comprised of a polyolefin, polyester, or polyamide. The finished product is rolled and delivered to the project site in a roll. On site, the material is unrolled over bare, prepared, seeded ground and secured with metal fasteners of varying type and properties.
The vegetation establishes through the mat, protecting the mat from sunlight (the degrading factor of the mat), while the mat protects the bare ground between the vegetation stems and protects the individual plant.
In sum, the composite of the human-formed material and natural vegetation yields a system greater than the sum of the components. This final system is permanent and able to withstand greater hydraulic forces than either component alone. One such technology is described in U.S. Pat. No. 7,820,560, with the patent protection afforded to the cross sectional shape of the fiber. An additional example of this technology is demonstrated in U.S. Pat. No. 5,849,645, which patents a particular type of advantageous netting.
A second technology exists that utilizes no netting, rather melt bonded or welded synthetic fibers. Long fibers are produced in a planar arrangement and heated to a temperature sufficient to melt-bond the individual fibers into a continuous, porous form. These mats have an advantage in a lack of netting, which can snag mowers or entrap wildlife. However, melt bonded products lack the inherent strength the netting provides. The product is produced into rolls and delivered and deployed in the same manner as stitch bonded products.
A third principle technology is a woven material. Specific weaving processes and techniques are utilized to create loft in the fabric, and thus, a three-dimensional web of protection for the vegetation. This class of products is created by weaving yarns into a continuous web. This arrangement yields the strongest, highest performing and longest lasting product class. Varieties of weave patterns, yarn types and treatments (heat shrinkage to form greater loft) have been utilized. An example of one such technology is cited in U.S. Pat. No. 5,567,087.
In order for a material to be classified as a permanent RECP, the material must maintain a permanent footprint and incorporate a measurable thickness of 0.25 inches (13 mm). As such, biodegradable or otherwise degradable components may not be utilized in the fabrication of TRM.
One significant problem with the prior art is the potential for ignition when the ground cover mat is exposed to heat or flame. The families of synthetic materials utilized for TRMs are not fire resistant. Chemical additives can improve the ignition resistance, however, such additives typically reduce the product's lifespan when exposed to sunlight. Even the few technologies that offer flame and ignition resistance and are UV stable offer little true resistance, in practical terms. When installed in roadside channels or on roadside slopes, particularly in arid climates, extreme temperatures, drought and plentiful ignition sources are cause for concern. Additionally, placement near important structures is dangerous, as the TRM adds a close-proximity fuel source, in the event of a wildfire, structure fire or other fire.
It is the object of the present invention to overcome the critical failures of current and past technologies while maintaining hydraulic and turf reinforcement performance.
It is a further object of the present invention to provide a finished product that is porous to allow for the growth of vegetation through the product.
It is a further object of the present invention to provide a mat that is flexible and conforms to the ground surface when installed.
It is a further object of the present invention to provide fiber and yarn with significantly greater specific gravity (˜2.7) rather than typical synthetic fibers and yarns (˜0.9).
It is a further object of the present invention to provide component fiber and yarn for the creation of mats/blankets that provide greater resistance to tensile loading, compared to synthetic fibers and yarn (strain rate).
It is a further object of the present invention to provide fiber derived components immune to decay from exposure to ultraviolet radiation, moisture, biologic activity, rot, mold or mildew.
It is a further object of the present invention to deploy an effective ignition, flame, smolder and fire resistant layer that provides erosion control in a cost effective manner.
It is a further object of the present invention to deploy an effective ignition, flame, smolder and fire resistant layer that provides turf reinforcement in a cost effective manner.
It is a further object of the present invention to provide a product that is easy to install, similar in means to conventional technologies.
It is a further object of the present invention to provide a product that is non-synthetic, in essence, natural, that meets the criteria qualify as a TRM.
It is a further object of the present invention to provide a product that is not derived from petrochemicals.
It is a further object of the present invention to provide an ignition, flame or fire resistant mat that may alternatively be used to protect the ground surface or other surface from flame, fire or ignition.
It is a further object of the present invention to provide an ignition, flame or fire proof mat that may alternatively be used to protect the ground surface or other surface from flame, fire or ignition.
It is a further object of the present invention to provide a component to a wildfire buffer system incorporating soil, the product and vegetation.